Performing file operations with cfftp

The cfftp tag lets you perform tasks on remote servers using File Transfer Protocol (FTP). You can use cfftp to cache connections for batch file transfers when uploading or downloading files.

Note: To use cfftp, select the Enable ColdFusion Security option on the Sandbox Security page in the Security area in the ColdFusion Administrator. (In the Standard Edition, select Security > Basic Security.)

For server/browser operations, use the cffile, cfcontent, and cfdirectory tags.
Using cfftp involves two major types of operations: connecting, and transferring files. The FTP protocol also provides commands for listing directories and performing other operations. For a complete list of attributes that support FTP operations and additional details on using the cfftp tag, see the CFML Reference.

Open an FTP connection and retrieve a file listing

Create a ColdFusion page with the following content:

<html>
<head>
<title>FTP Test</title>
</head>

<body>
<h1>FTP Test</h1>

<cfftp connection="Myftp"
server="MyServer"
username="MyUserName"
password="MyPassword"
action="Open"
stoponerror="Yes">


<cfftp connection=Myftp
action="GetCurrentDir"
stoponerror="Yes">


<cfoutput>
The current directory is:#cfftp.returnvalue#
</cfoutput>


<cfftp connection=Myftp
action="listdir"
directory="#cfftp.returnvalue#"
name="dirlist"
stoponerror="Yes">

<cfftp action="close" connection="Myftp">
Did the connection close successfully?
<cfoutput>#cfftp.succeeded#</cfoutput>


<hr>
FTP Directory Listing:

<cftable query="dirlist" colheaders="yes" htmltable>
<cfcol header="Name" TEXT="#name#">
<cfcol header="Path" TEXT="#path#">
<cfcol header="URL" TEXT="#url#">
<cfcol header="Length" TEXT="#length#">
<cfcol header="LastModified"
TEXT="#DateFormat(lastmodified)#">
<cfcol header="IsDirectory"
TEXT="#isdirectory#">
</cftable>

Change MyServer to the name of a server for which you have FTP permission.
Change MyUserName and MyPassword to a valid user name and password.To establish an anonymous connection, enter "anonymous" as the user name and an e-mail address (by convention) for the password.
Save the file as ftp_connect.cfm in the myapps directory under your web_root and view it in the web browser.

Reviewing the code

The following table describes the code and its function:

Code

Description

Open an FTP connection to the MyServer server and log on as MyUserName. If an error occurs, stop processing and display an error. You can use this connection in other cfftp tags by specifying the Myftp connection.

<cfftp connection=Myftp action="GetCurrentDir" stoponerror="Yes">
<cfoutput>
The current directory is: #cfftp.returnvalue#
</cfoutput>

Use the Myftp connection to get the name of the current directory; stop processing if an error occurs. Display the current directory.

Use the Myftp connection to get a directory listing. Use the value returned by the last cfftp call (the current directory of the connection) to specify the directory to list. Save the results in a variable named dirlist (a query object). Stop processing if an error occurs.

<cfftp action="close" connection="Myftp">
Did the connection close successfully?
<cfoutput>#cfftp.succeeded#</cfoutput>

Close the connection, and do not stop processing if the operation fails (because you can still use the results). Instead, display the value of the cfftp.succeeded variable, which is Yes if the connection is closed, and No if the operation failed.

Display a table with the results of the ListDir FTP command.

After you establish a connection with cfftp, you can reuse the connection to perform additional FTP operations until either you or the server closes the connection. When you access an already-active FTP connection, you need not respecify the user name, password, or server. In this case, make sure that when you use frames, only one frame uses the connection object.

Note: For a single simple FTP operation, such as GetFile or PutFile, you need not establish a connection. Specify all the necessary login information, including the server and any login and password, in the single cfftp request.

Caching connections across multiple pages

The FTP connection established by the cfftp tag is maintained only in the current page unless you explicitly assign the connection to a variable with Application or Session scope.
Assigning a cfftp connection to an application variable could cause problems, since multiple users could access the same connection object at the same time. Creating a session variable for a cfftp connection makes more sense, because the connection is available to only one client and does not last past the end of the session.

Example: caching a connection

In this example, the connection cache remains available to other pages within the current session. For this approach to work, enable session variables in your application, and lock code that uses session variables. For more information on locking, see Using Persistent Data and Locking.

Note: Changing connection characteristics, such the retrycount or timeout values, could require you to re-establish the connection.

Connection actions and attributes

The following table shows the available cfftp actions and the attributes they require when you use a named (that is, cached) connection. If you do not specify an existing connection name, specify the username, password, and server attributes.

Action	Attributes	Action	Attributes
Open	none	Rename	existingnew
Close	none	Remove	serveritem
ChangeDir	directory	GetCurrentDir	none
CreateDir	directory	GetCurrentURL	none
ListDir	namedirectory	ExistsDir	directory
RemoveDir	directory	ExistsFile	remotefile
GetFile	localfileremotefile	Exists	item
PutFile	localfileremotefile